TECHNICAL FIELD
[0001] The present invention relates to an article of manufacture, more explicitly to rotating
turbine blades or stationary turbine vanes for gas turbine engines, and in particular
to platforms of turbine blades or vanes.
BACKGROUND ART
[0002] In a turbomachine, such as a gas turbine engine, air is pressurized in a compressor
section and then mixed with fuel and burned in a combustor section to generate hot
combustion gases. The working medium, comprising hot combustion gases is expanded
within a turbine section of the engine where energy is extracted to power the compressor
section and to produce useful work, such as turning a generator to produce electricity.
The working medium travels through a series of turbine stages within the turbine section.
A turbine stage may include a row of stationary vanes, followed by a row of rotating
blades, where the blades extract energy from the hot combustion gases for providing
output.
[0003] A turbine blade or vane unit typically comprises at least one airfoil extending span-wise
from a platform. In some cases, for example, in stationary vanes, the airfoil(s) may
extend between two platforms, namely an outer diameter platform and an inner diameter
platform. Each platform has a pair of mate faces on laterally opposite ends, which
extend from a platform leading edge to a platform trailing edge. Each mate face of
the platform engages with an opposite mate face of a circumferentially adjacent blade
or vane unit, to form an assembly of a row of turbine blades or vanes. The platforms
define an endwall for a flow path of the working medium between circumferentially
adjacent airfoils.
[0004] A turbine blade or a vane unit may be manufactured, for example, by casting, which
may be optionally followed by a post-machining process. Manufacturing variation and
machining tolerances may lead to a step in the flow path at the interface of the mate
faces of the platforms of two circumferentially adjacent airfoils, which may potentially
affect engine performance.
[0005] EP 0 902 167 A1 discloses a segment arrangement for shroud bands, in particular in a gas turbine.
The segment arrangement comprises segments arranged next to one another and in each
case separated from one another by a gap. The hot-gas stream, in at least one section
of the gap, has a velocity component perpendicular to the direction of the gap from
a first segment to a second segment. In this case, in said section, along that edge
of the first segment which faces the gap, at least one film-cooling bore connects
a cooling-air chamber, allocated to the first segment, to the surface subjected to
the hot-gas stream.
[0006] Further,
EP 1 798 374 A2 discloses a turbine engine component, such as a turbine blade, which has an airfoil
portion, a plurality of cooling passages within the airfoil portion with each of the
cooling passages having an inlet for a cooling fluid. Each inlet has a flared bellmouth
inlet portion.
[0007] WO 20015/088699 A1 discloses an array of components in a gas turbine engine which include first and
second structures respectively including first and second surfaces that are arranged
adjacent to one another to provide a gap. The first and second surfaces respectively
have first and second rounded edges at the gap that are arranged in staggered relationship
relative to one another.
[0008] In
EP 1 674 659 A2 a turbine airfoil is disclosed which includes opposite pressure and suction sides
extending in span from a flowpath surface. The flowpath surface has chordally opposite
forward and aft edges and laterally opposite first and second endfaces corresponding
with the airfoil pressure and suction sides.
[0009] Further,
US 2013/0004315 A1 discloses a gas turbine engine. In gas turbine engines adjoining pairs of airfoil
structures include airfoils mounted to respective platforms. The platforms have side
edges defining mate faces that form a mate face gap extending from an upstream edge
of the platforms to a downstream edge of the platforms. A flow field of working gas
adjacent to endwalls of the platform comprises streamlines extending generally transverse
to the axial direction from a first airfoil toward an adjacent second airfoil. The
mate face gap has portions oriented transverse to the streamlines and oriented aligned
with the streamlines.
SUMMARY
[0010] Briefly, aspects of the present invention provide a chambered mate face for turbine
blades and vanes. The embodiments described may minimize impact of manufacturing variation
on engine performance.
[0011] According to the invention, an article of manufacture is provided as claimed in claim
1. Advantageous aspects of the invention are defined in the dependent claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The invention is shown in more detail by help of figures. The figures show specific
configurations and do not limit the scope of the invention.
FIG. 1 is a perspective view of a turbine blade usable in a gas turbine engine, where
embodiments of the present invention may be incorporated;
FIG. 2 is a schematic sectional view, looking in an axial direction of the gas turbine
engine, illustrating a forward facing step at a platform mat face caused by manufacturing
variation;
FIG. 3 is a schematic radial top view of a pair of turbine blades or vanes illustrating
an embodiment of the present invention;
FIG. 4 is a sectional view along the section IV-IV of FIG. 3;
FIG. 5 is a sectional view along the section V-V of FIG. 3; and
FIG. 6 is a sectional view, looking in a tangential direction, illustrating a wavy
mate face having a chamfered or filleted portion according to an embodiment of the
present invention.
DETAILED DESCRIPTION
[0013] In the following detailed description of the preferred embodiment, reference is made
to the accompanying drawings that form a part hereof, and in which is shown by way
of illustration, and not by way of limitation, a specific embodiment in which the
invention may be practiced. It is to be understood that other embodiments may be utilized
and that changes may be made without departing from the scope of the present invention.
[0014] In the description and drawings, the directional axes A, R and C respectively denote
an axial direction, a radial direction and a circumferential direction of a gas turbine
engine.
[0015] Referring now to FIG. 1, a turbine blade 10 is illustrated, wherein an embodiment
of the present invention may be implemented. The turbine blade 10 comprises an airfoil
12 extending span-wise radially outward from a platform 14 in relation to a rotation
axis A. The blade 10 further comprises a root portion 16 extending radially inward
from the platform 14, and being configured to attach the blade 10 to a rotor disk
(not shown). The airfoil 12 is formed of an outer wall 18 that delimits a generally
hollow airfoil interior. The outer wall 18 includes a generally concave pressure side
20 and a generally convex suction side 22, which are joined at an airfoil leading
edge 24 and at an airfoil trailing edge 26. The platform 14 comprises a radially outer
surface 15 defining a radially inner boundary for a flow path of a working medium.
The platform 14 thereby defines inner diameter endwall for the flow path. The platform
14 extends from a platform leading edge 28 to a platform trailing edge 30. The platform
14 also includes a first mate face 32 and a second mate face 34 spaced in a circumferential
or pitch-wise direction C. Each of the mate faces 32 and 34 extends from the platform
leading edge 28 to the platform trailing edge 30, with the first mate face 32 being
proximal to the suction side 22 of the airfoil 12 and the second mate face 34 being
proximal to the pressure side 20 of the airfoil 12. The mate faces 32 and 34 extend
radially inward from the radially outer surface 15 of the platform 14 and interface
with correspondingly opposite mate faces of circumferentially adjacent platforms to
form an assembly of a row of turbine blades.
[0016] FIG. 2 schematically illustrates a portion of an assembly 100 of a row of turbine
blades 10. The assembly 100 includes a first blade 10a having a first airfoil 12a
extending from a first platform 14a, and a circumferentially adjacent second blade
10b having a second airfoil 12b extending from a second platform 14b. The first platform
14a has a first mate face 32 proximal to the suction side 22 of the first airfoil
12a. The second platform has a second mate face 34 proximal to the pressure side 20
of the second airfoil 12b. The first and second mate faces 32 and 34 face each other
and are separated by a mate face gap G. In the shown example, the radial thickness
ta of the first mate face 32 is greater than a design mate thickness t within a manufacturing
tolerance, while, the radial thickness t
b of the second mate face 34 is lesser than the design mate thickness t within the
manufacturing tolerance. Such a manufacturing variation may lead to a step in the
flow path at the interface of the mate faces of the platforms of two circumferentially
adjacent blades.
[0017] It has been observed that at least in some regions of the flow path between circumferentially
adjacent blades, the mean velocity of the working medium is not purely axial but also
has a pitch-wise component, i.e., directed from one platform to the circumferentially
adjacent platform. In the example shown in FIG. 2, the mean velocity F of the working
medium at the given section has a component which is directed from the second platform
14b to the first platform 14a, whereby a forward facing step is defined at the interface
of the mate faces 32, 34. In general, a forward facing step may be said to formed
when the mate face of the downstream platform (in relation to the direction of the
mean velocity F) extends further into the flow path than the mate face of the upstream
platform. The present inventors have recognized that especially a forward facing step,
as shown in the example of FIG. 2, may cause aerodynamic losses and heat transfer
problems due to flow separation and vortex formation at the platform mate faces. Embodiments
of the present invention address at least the above described technical problem. In
particular, the embodiments illustrated in FIG. 3-5 are directed to providing a chamfer
and/or fillet along a portion of the mate face of one of the platforms, which is at
a downstream position with respect to a circumferentially adjacent platform, in relation
to the direction of the mean velocity of the working medium.
[0018] FIG. 3 illustrates portion of an assembly 100 of turbine blades 10 according to one
embodiment of the present invention. Each blade 10 may include one or more airfoils
12 extending from a platform 14. In the example shown, a first airfoil 12a extends
span-wise from a first platform 14a and a second airfoil 12b extends span-wise from
a second platform 14b circumferentially adjacent to the first platform 14a. Each of
the airfoils 12a, 12b comprises a respective outer wall 18 formed of a pressure side
20 and a suction side 22 joined at a respective airfoil leading edge 24 and at a respective
airfoil trailing edge 26. Each of the first and second platforms 14a and 14b extends
from a respective platform leading edge 28 to a respective platform trailing edge
30. Each of the platforms 14a and 14b further includes a pair of mate faces 32, 34
spaced in a circumferential or pitch-wise direction C. The pair of mate faces include
a first mate face 32 proximal to the suction side 22 of the respective airfoil 12a
or 12b, and a second mate face 34 proximal to the pressure side 20 of the respective
airfoil 12a or 12b. The first mate face 32 of the first platform 14a is parallel to
and faces the second mate face 34 of the second platform 14b along a platform splitline
80 extending between the platform leading and trailing edges 28, 30. A flow path for
a working medium is defined between the suction side 22 of the first airfoil 12a and
the pressure side 20 of the second airfoil 12b. The working medium flows in a generally
axial direction from the platform leading edge 28 to the platform trailing edge 30,
with the mean velocity varying in direction, as may be represented by the directional
arrow F for the purpose of illustration.
[0019] It has been observed that especially toward the aft end of the interface between
the mate faces 32, 34, the mean velocity F is typically directed from the second platform
14b to the first platform 14a, with the flow Mach numbers being highest near the platform
trailing edge 30. In the present embodiment, as shown in FIG. 4 with continued reference
to FIG. 3, the first mate face 32 of the first platform 14a may be chamfered or filleted
along an aft portion 36 thereof. In particular, the first mate face 32 may be chamfered
or filleted to an extent such that the chamfered or filleted portion 36 lies in a
region in the flow path where a mean velocity F of the working medium is directed
from the second platform 14b to the first platform 14a. The second mate face 34 of
the second platform 14b may be unchamfered and unfilleted along the extent thereof
that lies directly opposite to the chamfered or filleted portion 36 of the first mate
face 32 of the first platform 14a.
[0020] In particular, as shown in FIG. 3, the chamfered or filleted portion 36 of the first
mate face 32 of the first platform 14a extends from the platform trailing edge 30
of the first platform 14a to a first intermediate point 42 on the first mate face
32 of the first platform 14a. The first intermediate point 42 is located between the
platform leading edge 28 and the platform trailing edge 30 of the first platform 14a.
The location of the first intermediate point 42 may be based, for example, on the
determination of a point of inflection 82 on the first mate face 32. In an exemplary
embodiment, such a point 82 may be determined by first determining a point 90 of tangency
of a line 32' parallel to the first mate face 32 to the mean camber line 40 of one
of the airfoils, and projecting said point 90 on the first mate face 32 along the
circumferential direction C to locate the point 82 on the first mate face 32, as shown
in FIG. 3. The first intermediate point 42 on the first mate face 32 may lie at or
aft of the point 82. In other embodiments, the extent of the chamfered or filleted
portion 36 on the first mate face 32 may be determined by other means, including,
for example, consideration of flow velocities during engine operation.
[0021] As shown in FIG. 4, in one embodiment, the chamfered portion of the first mate face
32 of the first platform 14a comprises a chamfered surface 50 extending radially from
a first chamfer edge 52 to a second chamfer edge 54 at a chamfer angle α
1, which may be, for example and without limitation, 30 to 70 degrees, particularly
about 40 to 50 degrees, with respect to the radial direction R. In an alternate embodiment,
a similar technical effect may be realized by providing a fillet comprising a rounded
surface 50' (shown with dashed lines) with predefined radius r
1 extending between the edges 52, 54. The radial height t
1 of the chamfered or filleted surface 50, 50' may dependent on the manufacturing process
tolerances. In some embodiments, the chamfer height t
1 may range from 0.5% to 2% pitch distance of the blade/vane assembly. The chamfered
or filleted surface 50, 50' on the mate face 32 of the downstream platform 14a may
reduce flow separation and vortex formation at the interface of the mate faces 32,
34, thereby minimizing aerodynamic losses and heat transfer issues that may be potentially
caused by a forward facing step due to manufacturing variation. Referring to FIG.
3, the first mate face 32 of the second platform 14b may be provided with a similarly
chamfered or filleted portion 36 at an aft portion, while the second mate face 34
of the first platform 14a may be provided with a corresponding unchamfered and unfilleted
portion along an extent of the second mate face 34 that lies pitch-wise directly opposite
to the chamfered or filleted portion 36 of the first mate face 32.
[0022] In a further embodiment, as shown in FIG. 3 and 5, the second mate face 34 of the
second platform 14b may be chamfered or filleted along a forward portion 38 thereof.
This embodiment may be applicable to configurations in which the mean velocity F of
the working medium has a pitch-wise component directed from the first platform 14a
to the second platform 14b at a forward portion of the interface of the mate faces
32, 34. Accordingly, the second mate face 34 of the second platform 14b may be chamfered
or filleted to an extent such that that the chamfered or filleted portion 38 lies
in a region in the flow path where a mean velocity F of the working medium is directed
from the first platform 14a to the second platform 14b. The first mate face 32 of
the first platform 14a may be unchamfered and unfilleted along the extent thereof
that lies directly opposite to the chamfered or filleted portion 38 of the second
mate face 34 of the second platform 14b. The choice of having the chamfered (or filleted)
portion 38 on the second mate face 34 may depend, for example, on a combination of
blade geometry and engine flow parameters. For example, in some configurations, the
mean velocity in the flow path may be substantially axial in the forward portion,
whereby the need for chamfering or filleting a forward portion of the second mate
face 34 may be obviated.
[0023] In the illustrated embodiment as shown in FIG. 3, the chamfered or filleted portion
38 of the second mate face 34 of the second platform 14b extends between the platform
leading edge 28 of the second platform 14b and a second intermediate point 44 on the
second mate face 34 of the second platform 14b. The second intermediate point 44 is
located between the platform leading edge 28 and the platform trailing edge 30 of
the second platform 14b. The chamfered or filleted portion 38 of the second mate face
34 may extend all the way up to the platform leading edge 28 of the second platform
14b or may stop short at a distance therefrom. The location of the second intermediate
point 44 may be based, for example, on the determination of a point of inflection
84 on the second mate face 34. In an exemplary embodiment, such a point 84 may be
determined by first determining a point 90 of tangency of a line 34' parallel to the
second mate face 34 to the mean camber line 40 of one of the airfoils 12, and projecting
the point 90 on the second mate face 34 along the circumferential direction C to locate
the point 84 on the second mate face 34, as shown in FIG. 3. The second intermediate
point 44 on the second mate face 34 may lie at or forward of the point 84. In other
embodiments, the extent of the chamfered or filleted portion 38 on the second mate
face 34 may be determined by other means, including, for example, consideration of
flow velocities during engine operation.
[0024] As shown in FIG. 5, in one embodiment, the chamfered portion of the second mate face
34 of the second platform 14b comprises a chamfered surface 60 extending radially
from a first chamfer edge 62 to a second chamfer edge 64 at a chamfer angle α
2, which may be, for example and without limitation, 30 to 70 degrees, particularly
about 40 to 50 degrees, with respect to the radial direction R. In an alternate embodiment,
a similar technical effect may be realized by providing a fillet comprising a rounded
surface 60' (shown with dashed lines) with predefined radius r
2 extending between the edges 62, 64. The radial height t
2 of the chamfered or filleted surface 60, 60' may dependent on the manufacturing process
tolerances. In some embodiments, the chamfer height t
2 may range from 0.5% to 2% pitch distance of the blade/vane assembly. The chamfered
or filleted surface 60, 60' on the mate face 34 of the downstream platform 14b may
reduce flow separation and vortex formation at the interface of the mate faces 32,
34, thereby minimizing aerodynamic losses and heat transfer issues that may be potentially
caused by a forward facing step due to manufacturing variation. Referring to FIG.
3, the second mate face 34 of the first platform 14a may be provided with a similarly
chamfered or filleted portion 38 at a forward portion, while the first mate face 32
of the second platform 14b may be provided with a corresponding unchamfered and unfilleted
portion along an extent of the first mate face 32 that lies pitch-wise directly opposite
to the chamfered or filleted portion 38 of the second mate face 34.
[0025] In a still further embodiment, the platforms 14a, 14b may define a contoured endwall
facing the flow path, which is non-axisymmetric about the engine axis. In particular,
a non-axisymmetric endwall may comprise one or more hills 48 and /or troughs 46 formed
on the endwall, as shown by dashed lines in FIG. 3. A hill be may be defined as a
contour wherein the endwall extends into the flow path in relation to a nominal radius
of the endwall, whereas a trough may be defined as a contour wherein the endwall extends
away from the flow path in relation to the nominal radius of the end wall. In one
embodiment, at least one hill 48 and/or trough 46 may extend across the platform splitline
80, as shown in FIG. 3. In such a case, manufacturing variations caused by standard
tolerances may lead to a steeper forward facing step than in a configuration without
endwall contouring. The provision of a chamfer at the downstream platform is especially
advantageous for contoured endwalls, to maximize the aerodynamic benefits provided
by the contouring of the endwall. As shown in FIG. 6, on account of the non-axisymmetric
endwall contouring, the first mate face 32 and/or the second mate face 34 have a wavy
contour 70, in a direction from the platform leading edge 28 to the platform trailing
edge 30. The wavy contour 70 comprises a radial amplitude. In accordance with one
embodiment, the chamfered or filleted portions 36, 38 respectively of the first and
second mate faces 32, 34 may have a respective chamfer surface 50/50', 60/60' that
follows said wavy contour 70, that is, the first chamfer/fillet edge 52, 62 is parallel
to the respective second chamfer/fillet edge 54, 64, as shown in FIG. 6.
[0026] The above-described embodiments relate to inner diameter platforms of rotating turbine
blades, wherein the first and second platforms 14a and 14b define an inner diameter
endwall for the flow path of the working medium. In alternate embodiments, aspects
of the present invention may be applied to inner or outer diameter platforms of stationary
turbine vanes, wherein the platforms may define an inner or an outer diameter endwall
for the flow path of the working medium.
[0027] While specific embodiments have been described in detail, those with ordinary skill
in the art will appreciate that various modifications and alternative to those details
could be developed in light of the overall teachings of the disclosure. Accordingly,
the particular arrangements disclosed are meant to be illustrative only and not limiting
as to the scope of the invention, which is to be given the full breadth of the appended
claims.
1. An article of manufacture, wherein the article of manufacture is a turbine blade (10)
or a turbine vane, wherein the article of manufacture comprises:
at least one platform (14) of the turbine blade and the vane, respectively;
one or more airfoils (12) extending span-wise from the platform (14);
wherein each of said one or more airfoils (12) comprises an outer wall (18) formed
of a pressure side (20) and a suction side (22) joined at an airfoil leading edge
(24) and at an airfoil trailing edge (26),
wherein the platform (14) extends from a platform leading edge (28) to a platform
trailing edge (30),
wherein the platform (14) comprises a first mate face (32) and a second mate face
(34) spaced along a pitch-wise direction (C), the first mate face (32) being proximal
to the suction side (22) of one of the airfoils (12) and the second mate face (34)
being proximal to the pressure side (20) of the same airfoil (12) or a different airfoil
of said one or more airfoils (12), the first (32) and second (34) mate faces extending
between the platform leading edge (28) and the platform trailing edge (30),
wherein the first mate face (32) is chamfered or filleted along an aft portion (36)
thereof, the chamfered or filleted portion (36) of the first mate face (32) extending
from the platform trailing edge (30) to a first intermediate point (42) on the first
mate face (32) located between the platform leading edge (28) and the platform trailing
edge (30),
wherein the first (32) and the second (34) mate faces have a wavy contour (70) in
a direction from the respective platform leading edge (28) to the respective platform
trailing edge (30),
wherein the wavy contour (70) comprises a radial amplitude,
wherein a chamfered or filleted portion (36, 38) of the first mate face (32) and the
second mate face (34) have a chamfer or filleted surface (50, 60; 50', 60'),
wherein the chamfer surface (50, 60) of the first mate face (32) and the second mate
face (34) extends radially from a first chamfer edge (52, 62) to a second chamfer
edge (54, 64) of the first (32) and the second (34) mate faces at a chamfer angle
(α1, α2) with respect to the radial direction R, and
wherein the filleted surface (50', 60') of the first mate face (32) and the second
mate face (34) comprises a rounded surface (50', 60') extending between a first and
second fillet edge (52, 62; 54, 64),
wherein the chamfer or filleted surface (50, 60; 50', 60') of the first mate face
(32) and the second mate face (34) follows said wavy contour (70), wherein the first
chamfer edge (52, 62) is parallel to the second chamfer edge (54, 64) and the first
fillet edge (52, 62) is parallel to the second fillet edge (54, 64).
2. The article of manufacture (10) according to claim 1, wherein the first intermediate
point (42) lies at or aft of a point (82) of tangency of a line (32') parallel to
the first mate face (32) to a mean camber line (40) of the airfoil (12), as projected
on the first mate face (32) along the pitch-wise direction (C).
3. The article of manufacture (10) according to any of claims 1 and 2, wherein the second
mate face (34) is chamfered or filleted along a forward portion (38) thereof,
wherein the chamfered or filleted portion (38) of the second mate face (34) extends
partially or entirely between the platform leading edge (28) and a second intermediate
point (44) on the second mate face (34) located between the platform leading edge
(28) and the platform trailing edge (30) of the second platform (14b),
wherein the second intermediate point (44) lies at or forward of a point (84) of tangency
of a line (34') parallel to the second mate face (34) to a mean camber line (40) of
the airfoil (12), as projected on the second mate face (34) along the pitch-wise direction
(C).
4. The article of manufacture (10) according to any of claim 1 to 3, comprising
a first platform (14a) and a second platform (14b) of the turbine blade and the vane,
respectively;
a first airfoil (12a) extending span-wise from a first platform (14a) and a second
airfoil (12b) extending span-wise from a second platform (14b),
wherein each of the first (12a) and second (12b) airfoils comprises the respective
outer wall (18) formed of the pressure side (20) and the suction side (22) joined
at the respective airfoil leading edge (24) and at the respective airfoil trailing
edge (26),
wherein each of the first (14a) and second (14b) platforms extends from the respective
platform leading edge (28) to the respective platform trailing edge (30),
wherein the first platform (14a) comprises the first mate face (32) proximal to the
suction side (22) of the first airfoil (12a) and the second platform (14b) comprises
the second mate face (34) proximal to the pressure side (20) of the second airfoil
(12b), the first mate face (32) facing the second mate face (34) along a platform
splitline (80) extending between the platform leading (28) and trailing (30) edges
of the first (14a) and second (14b) platforms,
wherein a flow path for a working medium is defined between the suction side (22)
of the first airfoil (12a) and the pressure side (20) of the second airfoil (12b),
wherein the first mate face (32) is chamfered or filleted along the aft portion (36)
thereof, the chamfered or filleted portion (36) of the first mate face (32) lying
in a region in the flow path where a mean velocity (F) of the working medium is directed
from the second platform (14b) to the first platform (14a),
wherein the first (14a) and second (14b) platforms define a contoured endwall facing
the flow path, the contoured endwall being non-axisymmetric about a central axis (A)
of an assembly of turbine blades (10) or vanes, wherein the contoured endwall comprises
at least one trough (46) or hill (48) that extends across the platform splitline (80),
wherein the first (32) and the second (34) mate faces have the wavy contour (70) in
a direction from the respective platform leading edge (28) to the respective platform
trailing edge (30),
wherein the chamfered or filleted portion (36, 38) of the first mate face (32) and
the second mate face (34) have the respective chamfer surface (50/50', 60/60') that
follows said wavy contour (70).
5. The article of manufacture (10) according to claim 4, wherein the chamfered or filleted
portion (36) of the first mate face (32) extends from the platform trailing edge (30)
of the first platform (14a) to a first intermediate point (42) on the first mate face
(32) located between the platform leading edge (28) and the platform trailing edge
(30) of the first platform (14a).
6. The article of manufacture (10) according to claim 5, wherein the first intermediate
point (42) lies at or aft of a point (82) of tangency of a line (32') parallel to
the first mate face (32) to a mean camber line (40) of the first and second airfoils
(12a, 12b), as projected on the first mate face (32) along a circumferential direction
(C) of the assembly of turbine blades (10) or vanes.
7. The article of manufacture (10) according to any of claims 4 to 6, wherein second
mate face (34) is chamfered or filleted along a forward portion (38) thereof, the
chamfered or filleted portion (38) of the second mate face (34) lying in a region
in the flow path where a mean velocity (F) of the working medium is directed from
the first platform (14a) to the second platform (14b).
8. The article of manufacture (10) according to claim 7, wherein the chamfered or filleted
portion (38) of the second mate face (34) extends between the platform leading edge
(28) of the second platform (14b) and a second intermediate point (44) on the second
mate face (34) located between the platform leading edge (28) and the platform trailing
edge (30) of the second platform (14b).
9. The article of manufacture (10) according to claim 8, wherein the second intermediate
point (44) lies at or forward of a point (84) of tangency of a line (34') parallel
to the second mate face (34) to a mean camber line (40) of the first and second airfoils
(12a, 12b), as projected on the second mate face (34) along a circumferential direction
(C) of the assembly of turbine blades (10) or vanes.
10. The article of manufacture (10) according to any of claims 4 to 9, wherein the article
of manufacture (10) is the assembly of turbine blades, wherein the first and second
platforms define an inner diameter endwall for the flow path.
11. The article of manufacture (10) according to any of claims 4 to 9, wherein the article
of manufacture (10) is the assembly of turbine vanes, wherein the first and second
platforms define an inner or an outer diameter endwall for the flow path.
1. Herstellungsartikel, wobei der Herstellungsartikel eine Turbinenschaufel (10) oder
eine Turbinenleitschaufel ist,
wobei der Herstellungsartikel umfasst:
mindestens eine Plattform (14) der Turbinenschaufel bzw. der Leitschaufel;
ein oder mehrere Schaufelblätter (12), die sich spannweitenwärtig von der Plattform
(14) erstrecken;
wobei jedes des einen oder der mehreren Schaufelblätter (12) eine Außenwand (18) umfasst,
die aus einer Druckseite (20) und einer Saugseite (22) ausgebildet ist, die an einer
Schaufelblattvorderkante (24) und an einer Schaufelblatthinterkante (26) verbunden
sind,
wobei sich die Plattform (14) von einer Plattformvorderkante (28) zu einer Plattformhinterkante
(30) erstreckt,
wobei die Plattform (14) eine erste Passfläche (32) und eine zweite Passfläche (34)
umfasst, die entlang einer Steigungsrichtung (C) beabstandet sind, wobei die erste
Passfläche (32) proximal zu der Saugseite (22) eines der Schaufelblätter (12) ist
und die zweite Passfläche (34) proximal zu der Druckseite (20) desselben Schaufelblatts
(12) oder eines anderen Schaufelblatts des einen oder der mehreren Schaufelblätter
(12) ist, wobei sich die ersten (32) und zweiten (34) Passflächen zwischen der Plattformvorderkante
(28) und der Plattformhinterkante (30) erstrecken,
wobei die erste Passfläche (32) entlang eines hinteren Abschnitts (36) davon gefast
oder gekehlt ist, wobei sich der gefaste oder gekehlte Abschnitt (36) der ersten Passfläche
(32) von der Plattformhinterkante (30) zu einem ersten Zwischenpunkt (42) auf der
ersten Passfläche (32) erstreckt, der sich zwischen der Plattformvorderkante (28)
und der Plattformhinterkante (30) befindet,
wobei die ersten (32) und die zweiten (34) Passflächen eine wellenförmige Kontur (70)
in einer Richtung von der jeweiligen Plattformvorderkante (28) zu der jeweiligen Plattformhinterkante
(30) aufweisen, wobei die wellenförmige Kontur (70) eine radiale Amplitude umfasst,
wobei ein gefaster oder gekehlter Abschnitt (36, 38) der ersten Passfläche (32) und
der zweiten Passfläche (34) eine gefaste oder gekehlte Oberfläche (50, 60; 50', 60')
aufweist,
wobei sich die Fasenoberfläche (50, 60) der ersten Passfläche (32) und der zweiten
Passfläche (34) radial von einer ersten Fasenkante (52, 62) zu einer zweiten Fasenkante
(54, 64) der ersten (32) und der zweiten (34) Passflächen in einem Fasenwinkel (α1, α2) in Bezug auf die radiale Richtung R erstreckt, und
wobei die gekehlte Oberfläche (50', 60') der ersten Passfläche (32) und der zweiten
Passfläche (34) eine abgerundete Oberfläche (50', 60') umfasst, die sich zwischen
einer ersten und zweiten Kehlungskante (52, 62; 54, 64) erstreckt,
wobei die gefaste oder gekehlte Oberfläche (50, 60; 50', 60') der ersten Passfläche
(32) und der zweiten Passfläche (34) der wellenförmigen Kontur (70) folgt, wobei die
erste Fasenkante (52, 62) parallel zu der zweiten Fasenkante (54, 64) ist und die
erste Kehlungskante (52, 62) parallel zu der zweiten Kehlungskante (54, 64) ist.
2. Herstellungsartikel (10) nach Anspruch 1, wobei der erste Zwischenpunkt (42) an oder
hinter einem Tangentialpunkt (82) einer Linie (32') parallel zu der ersten Passfläche
(32) zu einer mittleren Krümmungslinie (40) des Schaufelblatts (12), projiziert auf
der ersten Passfläche (32) entlang der Steigungsrichtung (C), liegt.
3. Herstellungsartikel (10) nach einem der Ansprüche 1 und 2, wobei die zweite Passfläche
(34) entlang eines vorderen Abschnitts (38) davon gefast oder gekehlt ist,
wobei sich der gefaste oder gekehlte Abschnitt (38) der zweiten Passfläche (34) teilweise
oder vollständig zwischen der Plattformvorderkante (28) und einem zweiten Zwischenpunkt
(44) auf der zweiten Passfläche (34) erstreckt, der sich zwischen der Plattformvorderkante
(28) und der Plattformhinterkante (30) der zweiten Plattform (14b) befindet,
wobei der zweite Zwischenpunkt (44) an oder vor einem Tangentialpunkt (84) einer Linie
(34') parallel zu der zweiten Passfläche (34) zu einer mittleren Krümmungslinie (40)
des Schaufelblatts (12), projiziert auf der zweiten Passfläche (34) entlang der Steigungsrichtung
(C), liegt.
4. Herstellungsartikel (10) nach einem der Ansprüche 1 bis 3, umfassend
eine erste Plattform (14a) und eine zweite Plattform (14b) der Turbinenschaufel bzw.
der Leitschaufel;
ein erstes Schaufelblatt (12a), das sich spannweitenwärtig von einer ersten Plattform
(14a) erstreckt, und ein zweites Schaufelblatt (12b), das sich spannweitenwärtig von
einer zweiten Plattform (14b) erstreckt,
wobei jedes der ersten (12a) und zweiten (12b) Schaufelblätter die jeweilige Außenwand
(18) umfasst, die aus der Druckseite (20) und der Saugseite (22) ausgebildet ist,
die an der jeweiligen Schaufelblattvorderkante (24) und an der jeweiligen Schaufelblatthinterkante
(26) verbunden sind,
wobei sich jede der ersten (14a) und zweiten (14b) Plattformen von der jeweiligen
Plattformvorderkante (28) zu der jeweiligen Plattformhinterkante (30) erstreckt,
wobei die erste Plattform (14a) die erste Passfläche (32) proximal zu der Saugseite
(22) des ersten Schaufelblatts (12a) umfasst und die zweite Plattform (14b) die zweite
Passfläche (34) proximal zu der Druckseite (20) des zweiten Schaufelblatts (12b) umfasst,
wobei die erste Passfläche (32) der zweiten Passfläche (34) entlang einer Plattformteilungslinie
(80) zugewandt ist, die sich zwischen den Plattformvorder- (28) und -hinter(30)-Kanten
der ersten (14a) und zweiten (14b) Plattformen erstreckt,
wobei ein Strömungsweg für ein Arbeitsmedium zwischen der Saugseite (22) des ersten
Schaufelblatts (12a) und der Druckseite (20) des zweiten Schaufelblatts (12b) definiert
ist,
wobei die erste Passfläche (32) entlang des hinteren Abschnitts (36) davon gefast
oder gekehlt ist, wobei der gefaste oder gekehlte Abschnitt (36) der ersten Passfläche
(32) in einer Region in dem Strömungsweg liegt, wo eine mittlere Geschwindigkeit (F)
des Arbeitsmediums von der zweiten Plattform (14b) zu der ersten Plattform (14a) gerichtet
ist,
wobei die ersten (14a) und zweiten (14b) Plattformen eine konturierte Endwand definieren,
die dem Strömungsweg zugewandt ist, wobei die konturierte Endwand nicht-achsensymmetrisch
um eine Mittelachse (A) einer Baugruppe von Turbinenschaufeln (10) oder Leitschaufeln
ist, wobei die konturierte Endwand mindestens eine Vertiefung (46) oder Erhöhung (48)
umfasst, die sich über die Plattformteilungslinie (80) erstreckt,
wobei die ersten (32) und die zweiten (34) Passflächen die wellenförmige Kontur (70)
in einer Richtung von der jeweiligen Plattformvorderkante (28) zu der jeweiligen Plattformhinterkante
(30) aufweisen,
wobei der gefaste oder gekehlte Abschnitt (36, 38) der ersten Passfläche (32) und
der zweiten Passfläche (34) die jeweilige Fasenoberfläche (50/50', 60/60') aufweist,
die der wellenförmigen Kontur (70) folgt.
5. Herstellungsartikel (10) nach Anspruch 4, wobei sich der gefaste oder gekehlte Abschnitt
(36) der ersten Passfläche (32) von der Plattformhinterkante (30) der ersten Plattform
(14a) zu einem ersten Zwischenpunkt (42) an der ersten Passfläche (32) erstreckt,
der sich zwischen der Plattformvorderkante (28) und der Plattformhinterkante (30)
der ersten Plattform (14a) befindet.
6. Herstellungsartikel (10) nach Anspruch 5, wobei der erste Zwischenpunkt (42) an oder
hinter einem Tangentialpunkt (82) einer Linie (32') parallel zu der ersten Passfläche
(32) zu einer mittleren Krümmungslinie (40) der ersten und zweiten Schaufelblätter
(12a, 12b), projiziert auf der ersten Passfläche (32) entlang einer Umfangsrichtung
(C) der Baugruppe von Turbinenschaufeln (10) oder Leitschaufeln, liegt.
7. Herstellungsartikel (10) nach einem der Ansprüche 4 bis 6, wobei die zweite Passfläche
(34) entlang eines vorderen Abschnitts (38) davon gefast oder gekehlt ist, wobei der
gefaste oder gekehlte Abschnitt (38) der zweiten Passfläche (34) in einer Region in
dem Strömungsweg liegt, wo eine mittlere Geschwindigkeit (F) des Arbeitsmediums von
der ersten Plattform (14a) zu der zweiten Plattform (14b) gerichtet ist.
8. Herstellungsartikel (10) nach Anspruch 7, wobei sich der gefaste oder gekehlte Abschnitt
(38) der zweiten Passfläche (34) zwischen der Plattformvorderkante (28) der zweiten
Plattform (14b) und einem zweiten Zwischenpunkt (44) auf der zweiten Passfläche (34)
erstreckt, der sich zwischen der Plattformvorderkante (28) und der Plattformhinterkante
(30) der zweiten Plattform (14b) befindet.
9. Herstellungsartikel (10) nach Anspruch 8, wobei der zweite Zwischenpunkt (44) an oder
vor einem Tangentialpunkt (84) einer Linie (34') parallel zu der zweiten Passfläche
(34) zu einer mittleren Krümmungslinie (40) der ersten und zweiten Schaufelblätter
(12a, 12b), projiziert auf der zweiten Passfläche (34) entlang einer Umfangsrichtung
(C) der Baugruppe von Turbinenschaufeln (10) oder Leitschaufeln, liegt.
10. Herstellungsartikel (10) nach einem der Ansprüche 4 bis 9, wobei der Herstellungsartikel
(10) die Baugruppe von Turbinenschaufeln ist, wobei die ersten und zweiten Plattformen
eine Innendurchmesserendwand für den Strömungsweg definieren.
11. Herstellungsartikel (10) nach einem der Ansprüche 4 bis 9, wobei der Herstellungsartikel
(10) die Baugruppe von Turbinenleitschaufeln ist, wobei die ersten und zweiten Plattformen
eine Innen- oder eine Außendurchmesserendwand für den Strömungsweg definieren.
1. Article de fabrication, dans lequel l'article de fabrication est une aube de turbine
(10) ou une ailette de turbine,
dans lequel l'article de fabrication comprend :
au moins une plate-forme (14) de l'aube de turbine et de l'ailette, respectivement
;
un ou plusieurs profils aérodynamiques (12) s'étendant dans le sens de l'envergure
depuis la plate-forme (14) ;
dans lequel chacun desdits un ou plusieurs profils aérodynamiques (12) comprend une
paroi extérieure (18) formée d'un côté refoulement (20) et d'un côté aspiration (22)
joints au niveau d'un bord d'attaque de profil aérodynamique (24) et au niveau d'un
bord de fuite de profil aérodynamique (26),
dans lequel la plate-forme (14) s'étend depuis un bord d'attaque de plate-forme (28)
jusqu'à un bord de fuite de plate-forme (30),
dans lequel la plate-forme (14) comprend une première face d'accouplement (32) et
une seconde face d'accouplement (34) espacées le long d'un sens de pas (C), la première
face d'accouplement (32) étant proximale au côté aspiration (22) d'un des profils
aérodynamiques (12) et la seconde face d'accouplement (34) étant proximale au côté
refoulement (20) du même profil aérodynamique (12) ou d'un profil aérodynamique différent
desdits un ou plusieurs profils aérodynamiques (12), les première (32) et seconde
(34) faces d'accouplement s'étendant entre le bord d'attaque de plate-forme (28) et
le bord de fuite de plate-forme (30),
dans lequel la première face d'accouplement (32) est en chanfrein ou en congé le long
d'une partie arrière (36) de celle-ci, la partie en chanfrein ou en congé (36) de
la première face d'accouplement (32) s'étendant depuis le bord de fuite de plate-forme
(30) jusqu'à un premier point intermédiaire (42), sur la première face d'accouplement
(32), situé entre le bord d'attaque de plate-forme (28) et le bord de fuite de plate-forme
(30),
dans lequel la première (32) et la seconde (34) faces d'accouplement ont un contour
ondulé (70) dans une direction depuis le bord d'attaque de plate-forme respectif (28)
jusqu'au bord de fuite de plate-forme respectif (30),
dans lequel le contour ondulé (70) comprend une amplitude radiale,
dans lequel une partie en chanfrein ou en congé (36, 38) de la première face d'accouplement
(32) et de la seconde face d'accouplement (34) a une surface en chanfrein ou en congé
(50, 60 ; 50', 60'),
dans lequel la surface en chanfrein (50, 60) de la première face d'accouplement (32)
et de la seconde face d'accouplement (34) s'étend radialement depuis un premier bord
de chanfrein (52, 62) jusqu'à un second bord de chanfrein (54, 64) de la première
(32) et de la seconde (34) faces d'accouplement à un angle de chanfrein (α1, α2) par rapport à la direction radiale R, et
dans lequel la surface en congé (50', 60') de la première face d'accouplement (32)
et de la seconde face d'accouplement (34) comprend une surface arrondie (50', 60')
s'étendant entre un premier et un second bord de congé (52, 62 ; 54, 64),
dans lequel la surface en chanfrein ou en congé (50, 60 ; 50', 60') de la première
face d'accouplement (32) et de la seconde face d'accouplement (34) suit ledit contour
ondulé (70), dans lequel le premier bord de chanfrein (52, 62) est parallèle au second
bord de chanfrein (54, 64) et le premier bord de congé (52, 62) est parallèle au second
bord de congé (54, 64).
2. Article de fabrication (10) selon la revendication 1, dans lequel le premier point
intermédiaire (42) se trouve à un point (82), ou à l'arrière de ce dernier, de tangence
d'une ligne (32'), parallèle à la première face d'accouplement (32), par rapport à
une ligne de cambrure moyenne (40) du profil aérodynamique (12), telle que projetée
sur la première face d'accouplement (32) le long de la sens de pas (C).
3. Article de fabrication (10) selon l'une quelconque des revendications 1 et 2, dans
lequel la seconde face d'accouplement (34) est en chanfrein ou en congé le long d'une
partie avant (38) de celle-ci,
dans lequel la partie en chanfrein ou en congé (38) de la seconde face d'accouplement
(34) s'étend partiellement ou entièrement entre le bord d'attaque de plate-forme (28)
et un second point intermédiaire (44), sur la seconde face d'accouplement (34), situé
entre le bord d'attaque de plate-forme (28) et le bord de fuite de plate-forme (30)
de la seconde plate-forme (14b),
dans lequel le second point intermédiaire (44) se trouve à un point (84), ou à l'avant
de ce dernier, de tangence d'une ligne (34'), parallèle à la seconde face d'accouplement
(34), par rapport à une ligne de cambrure moyenne (40) du profil aérodynamique (12),
telle que projetée sur la seconde face d'accouplement (34) le long de la sens de pas
(C).
4. Article de fabrication (10) selon l'une quelconque des revendications 1 à 3, comprenant
une première plate-forme (14a) et une seconde plate-forme (14b) de l'aube de turbine
et de l'ailette, respectivement ;
un premier profil aérodynamique (12a) s'étendant dans le sens de l'envergure depuis
une première plate-forme (14a) et un second profil aérodynamique (12b) s'étendant
dans le sens de l'envergure depuis une seconde plate-forme (14b),
dans lequel chacun des premier (12a) et second (12b) profils aérodynamiques comprend
la paroi extérieure respective (18) formée du côté refoulement (20) et du côté aspiration
(22) joints au niveau du bord d'attaque de profil aérodynamique respectif (24) et
au niveau du bord de fuite de profil aérodynamique respectif (26),
dans lequel chacune des première (14a) et seconde (14b) plates-formes s'étend depuis
le bord d'attaque de plate-forme respectif (28) jusqu'au bord de fuite de plate-forme
respectif (30),
dans lequel la première plate-forme (14a) comprend la première face d'accouplement
(32) proximale au côté aspiration (22) du premier profil aérodynamique (12a) et la
seconde plate-forme (14b) comprend la seconde face d'accouplement (34) proximale au
côté refoulement (20) du second profil aérodynamique (12b), la première face d'accouplement
(32) faisant face à la seconde face d'accouplement (34) le long d'une ligne de division
de plate-forme (80) s'étendant entre les bords d'attaque (28) et de fuite (30) de
plate-forme des première (14a) et seconde (14b) plates-formes,
dans lequel un chemin d'écoulement pour un fluide de travail est défini entre le côté
aspiration (22) du premier profil aérodynamique (12a) et le côté refoulement (20)
du second profil aérodynamique (12b),
dans lequel la première face d'accouplement (32) est en chanfrein ou en congé le long
de la partie arrière (36) de celle-ci, la partie en chanfrein ou en congé (36) de
la première face d'accouplement (32) se trouvant dans une région dans le chemin d'écoulement
où une vitesse moyenne (F) du fluide de travail est dirigée depuis la seconde plate-forme
(14b) vers la première plate-forme (14a),
dans lequel les première (14a) et seconde (14b) plates-formes définissent une paroi
d'extrémité profilée faisant face au chemin d'écoulement, la paroi d'extrémité profilée
étant non axisymétrique autour d'un axe central (A) d'un ensemble d'aubes (10) ou
d'ailettes de turbine, dans lequel la paroi d'extrémité profilée comprend au moins
un enfoncement (46) ou une saillie (48) qui s'étend à travers la ligne de division
de plate-forme (80),
dans lequel la première (32) et la seconde (34) faces d'accouplement ont le contour
ondulé (70) dans une direction depuis le bord d'attaque de plate-forme respectif (28)
jusqu'au bord de fuite de plate-forme respectif (30),
dans lequel la partie en chanfrein ou en congé (36, 38) de la première face d'accouplement
(32) et de la seconde face d'accouplement (34) a la surface en chanfrein respective
(50/50', 60/60') qui suit ledit contour ondulé (70).
5. Article de fabrication (10) selon la revendication 4, dans lequel la partie en chanfrein
ou en congé (36) de la première face d'accouplement (32) s'étend depuis le bord de
fuite de plate-forme (30) de la première plate-forme (14a) jusqu'à un premier point
intermédiaire (42), sur la première face d'accouplement (32), situé entre le bord
d'attaque de plate-forme (28) et le bord de fuite de plate-forme (30) de la première
plate-forme (14a).
6. Article de fabrication (10) selon la revendication 5, dans lequel le premier point
intermédiaire (42) se trouve à un point (82), ou à l'arrière de ce dernier, de tangence
d'une ligne (32'), parallèle à la première face d'accouplement (32), par rapport à
une ligne de cambrure moyenne (40) des premier et second profils aérodynamiques (12a,
12b), telle que projetée sur la première face d'accouplement (32) le long d'une direction
circonférentielle (C) de l'ensemble d'aubes (10) ou d'ailettes de turbine.
7. Article de fabrication (10) selon l'une quelconque des revendications 4 à 6, dans
lequel la seconde face d'accouplement (34) est en chanfrein ou en congé le long d'une
partie avant (38) de celle-ci, la partie en chanfrein ou en congé (38) de la seconde
face d'accouplement (34) se trouvant dans une région dans le chemin d'écoulement où
une vitesse moyenne (F) du fluide de travail est dirigée depuis la première plate-forme
(14a) vers la seconde plate-forme (14b).
8. Article de fabrication (10) selon la revendication 7, dans lequel la partie en chanfrein
ou en congé (38) de la seconde face d'accouplement (34) s'étend entre le bord d'attaque
de plate-forme (28) de la seconde plate-forme (14b) et un second point intermédiaire
(44), sur la seconde face d'accouplement (34), situé entre le bord d'attaque de plate-forme
(28) et le bord de fuite de plate-forme (30) de la seconde plate-forme (14b).
9. Article de fabrication (10) selon la revendication 8, dans lequel le second point
intermédiaire (44) se trouve à un point (84), ou à l'avant de ce dernier, de tangence
d'une ligne (34'), parallèle à la seconde face d'accouplement (34), par rapport à
une ligne de cambrure moyenne (40) des premier et second profils aérodynamiques (12a,
12b), telle que projetée sur la seconde face d'accouplement (34) le long d'une direction
circonférentielle (C) de l'ensemble d'aubes (10) ou ailettes de turbine.
10. Article de fabrication (10) selon l'une quelconque des revendications 4 à 9, dans
lequel l'article de fabrication (10) est l'ensemble d'aubes de turbine, dans lequel
les première et seconde plates-formes définissent une paroi d'extrémité diamétrale
intérieure pour le chemin d'écoulement.
11. Article de fabrication (10) selon l'une quelconque des revendications 4 à 9, dans
lequel l'article de fabrication (10) est l'ensemble d'ailette de turbines, dans lequel
les première et seconde plates-formes définissent une paroi d'extrémité diamétrale
intérieure ou extérieure pour le chemin d'écoulement.